Name

scalb, scalbf, scalbl, scalbn, scalbnf, scalbnl, scalbln, scalblnf, scalblnl — multiply floating-point number by integral power of radix

Synopsis

#include <math.h>
double scalb( double   x,
  double   exp);
float scalbf( float   x,
  double   exp);
long double scalbl( long double   x,
  double   exp);
double scalbn( double   x,
  int   exp);
float scalbnf( float   x,
  int   exp);
long double scalbnl( long double   x,
  int   exp);
double scalbln( double   x,
  long int   exp);
float scalblnf( float   x,
  long int   exp);
long double scalblnl( long double   x,
  long int   exp);
[Note] Note
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
scalb(), scalbf(), scalbl():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 500
scalbn(), scalbnf(), scalbnl():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE;
or cc -std=c99
scalbln(), scalblnf(), scalblnl():
_XOPEN_SOURCE >= 600 || _ISOC99_SOURCE;
or cc -std=c99
[Note] Note

Link with −lm.

DESCRIPTION

These functions multiply their first argument x by FLT_RADIX (probably 2) to the power exp.

If FLT_RADIX equals 2, then scalbn() is equivalent to ldexp(3).

The value of FLT_RADIX is found in <float.h>

CONFORMING TO

The scalb() function is from 4.3BSD. The scalbn() and scalbln() functions are from C99. All three are in POSIX.1-2001. The scalb() function is marked obsolescent.

SEE ALSO

ldexp(3)

COLOPHON

This page is part of release 2.79 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.


  Copyright 2004 Andries Brouwer <aebcwi.nl>.

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